ML520G72 638nm 500mw Diode Group Buy

[pullbangdead]

There is a lot of the beam getting clipped in the second and third photos, hence the apparent better divergence, and much lower power!

Yep, still ok with me, power to spare in this little thing for what I have in mind.

250mW is plenty for me, and even though I'm losing a good bit of the emitted light to get 250mW out of the lens, this is still the cheapest way I've seen to achieve that objective.

But I know others need/want better.

[danielbriggs]

I'd put a fiver on this lens being half decent:
http://www.thorlabs.de/thorProduct.c...umber=A390TM-A



Cheaper direct from Roithner....

[jaycey]

Has anyone ever enquired about custom lens from companies such as Thorlabs or Roithner?

[andyf97]

Any timeline yet? I would love to get cookin' with one of these things.

The "list" hasn't been updated for ~10 days it seems.

Been away touring and the first real day back to work, I will be updating the other thread http://www.photonlexicon.com/forums/...Group-Buy-list

Later today or tomorrow.

[andyf97]

Dave, and everyone else.

You have no chance to do it with a single lens.

You need to use at least 3 depending on the desired beam spec.

The first thing to do is adjust both axis so you don't loos power due to beam clipping, then you can start to consider the beam collimation. One lens is simply not enough.

For 1mrad 3mm you need 3 lenses, in the improved beam spec it is required 4 lenses two of which are only for initial beam adjustment. All the lenses required are custom cylindrical. The first two adjustment lenses are very tiny units of 2mm x 3mm.

Why don't we see all the laser projectors running out to buy these diodes is simple, the costs for them would be higher as they will be buying thousands of op next diodes and generally go for what is proven to work. The mitsu diode although more tricky to use especially in a mass knife edging system, has many advantages of the other options and I am sure once the laser projector producers have sold all there stocks of op next, I am sure we will start to see more and more mitsu diodes appearing in modules.

I am rushing another Blue moving head out today as its sitting there waiting to be done, then starting monday I plan to be 100% onto this red.

Dave thank you for your time and effort to do some tests but really if you knew what you were doing you would not waste time with one single lens.

Well I got a sample on Friday, and have spent a little time playing round with lenses I have here.. as seem below, the results are a little disappointing. Just a little!!

OK, here goes.

First lens up - Thor C110TME - Focal length 6.24mm
Attachment 18712Attachment 18711
Beam size at aperture, around 5mm by 1mm. drive current, 525ma, output power 375mw.

Second lens up - Creative laser technologies, glass lens, ar coated
Attachment 18713Attachment 18714
Beam size at aperture, about 5mm by 1mm. Drive current 525ma, output power 240mw.

Third lens up - Aixiz glass
Attachment 18715Attachment 18716
Beam size at aperture, about 5mm by 1mm. Drive current 525ma, output power 215mw



Pretty clear the NA of the second 2 lenses is not up to the task, and a lot of that ugly stripe is getting clipped by the lenses.

So with a good lens, who likes 6mrad with no correction? ( I got 2mrad with the same focal length lens with a 445nm diode ) I tried with some prisms, and they work, but the losses are a lot higher than 445nm.

Something else I tried was masking off the lower power fringes along the length of the stripe, leaving only the higher power portion of the beam in a 5 x 1mm rectangle. Unfortunately, there is quite a bit of power in the side fringes. Masking the Thor lens dropped around 150mw off the total power.

Conclusion: Does anybody want a red flashlight? We have one for sale cheap!! Seriously I give up!

[dave]

Time for you to put pictures where your words are then!

[andyf97]

Time for you to put pictures where your words are then!

Will be this week.

[p1t8ull]

A 3mm/1mR beam sounds just about good enough..

I was under the impression the diameter/divegence relationship curse remained no matter how many conventional lenses you use to collimate a diode, so I'm looking forward to the specifics of how this is done

[catalanjo]

I am rushing another Blue moving head out today as its sitting there waiting to be done, then starting monday I plan to be 100% onto this red.

Hi Andy,
Isn't a moving head 1000mw blue just a tad dangerous?


Thanks for last weeks PM. Like Simon I am very interested in the details of your mitsu lens setup.
I thought that the beam spec limits must be set by emitter dimensions!

Could these lenses be combined into a GRIN

Cheers

[badger1666]

I think you will find it's a lot more than a 1w if the last one is anything to go by
Check the video of the last one out